Plastic buckling of rectangular plates subjected to intermediate and end inplane loads

This paper is concerned with the plastic buckling of rectangular plates subjected to both intermediate and end uniaxial loads. The plate has two opposite simply supported edges that are parallel to the load direction while the other remaining edges may take any combination of free, simply supported or clamped conditions. Both the incremental theory of plasticity and the deformation theory of plasticity are considered in bounding the plastic behaviour of the plate. The buckling problem is solved by decomposing the plate into two sub-plates at the boundary where the intermediate load acts. Each sub-plate buckling problem is solved exactly using the Levy approach and the two solutions brought together by the continuity equations at the separated interface. There are eight possible solutions for each sub-plate and consequently there are 64 combinations of solutions to be considered for the entire plate. The final solution combination depends on the nature of the ratio of the intermediate load to the end load, the intermediate load location, aspect ratio, and material properties. Typical plastic stability criteria are presented in graphical forms which should be useful for engineers designing plated walls that support intermediate floors/loads.